Carmella just planted seeds for her vegetable garden. Anxious to view the progress of her plants, she checks her garden one afternoon, but sees that 4 weeds she has never seen before are growing in her vegetable garden. After a few weeks, she notices that the number of weeds appears to be tripling each week. If she doesn’t do something, she calculates that there could soon be 972 weeds in her garden. If represents the number of weeks, which equation could be used to determine what week Carmella would expect to find 972 weeds in her garden: